Hi Ian,
I didn't think there was a problem with the aluminium tube, just the fact the insert tube flexes in the foam. I thought it might tear through the surface. Maybe the fact that the twat I had doing the work on the plane did damage to the wings by leaving them in the sun...(not to mention all bad work he did)....

As you know they were left in the sun and split the veneer.
I put the thread on here only to confirm my suspicions , if no one had problems then maybe the foam is a bit more spongy in places because of the sun expanding it.... I don't know... but it does flex a lot with very little weight..

It's not far from being covered, taken a shed load of hours to get to this point though... No thanks to that wanker that called himself a "professional commission model plane builder"

Anyway thanks for your help, don't take it personally.